An inkjet printer typically includes one or more printheads and their corresponding ink supplies. A printhead includes an array of drop ejectors, each ejector includes an ink chamber, an ejecting actuator and a nozzle through which droplets of ink are ejected. The ejecting actuator may be one of various types, including a heater that vaporizes some of the ink in the chamber in order to propel a droplet out of the nozzle, or a piezoelectric device which changes the wall geometry of the chamber in order to produce a pressure wave that ejects a droplet. The droplets are typically directed toward paper or other recording medium in order to produce an image according to image data that is converted into electronic firing pulses for the drop ejectors as the print medium is moved relative to the printhead.
Ink is provided to the printhead through an inlet port of the printhead. In some printers the corresponding ink supply can be located remotely from the printhead and connected to it, for example by tubing. Alternatively in other printers, an ink supply, also called an ink tank or ink reservoir, can be directly coupled to the printhead. For the case of ink tanks mounted on the carriage of a carriage printer, the ink tank can be permanently mounted onto the printhead, so that the printhead needs to be replaced when the ink is depleted, or the ink tank can be detachably mounted onto the printhead, so that only the ink tank itself needs to be replaced when the ink tank is depleted. Carriage mounted ink tanks typically contain only enough ink for up to about several hundred prints. This is because the total mass of the carriage needs be limited, so that accelerations of the carriage at each end of the travel do not result in large forces that can shake the printer back and forth. As a result, users of carriage printers having detachably mounted ink tanks need to replace the ink tanks periodically, depending on their printing usage, typically several times per year. An ink tank design facilitating easy and clean installation of a detachable ink tank is beneficial.
Inkjet ink includes a variety of volatile and nonvolatile components including pigments or dyes, humectants, image durability enhancers, and carriers or solvents. For proper operation of the inkjet printhead it is important that the ink transferred from the outlet port of the ink tank to the inlet port of the printhead have the appropriate balance of these ink components. Therefore, during shipping and storage of an inkjet ink tank it is common practice to provide a seal over the outlet port(s) of the ink tank in order to inhibit the evaporative loss of the volatile components of the ink. U.S. Pat. No. 6,464,339 discloses a removable seal that is adhesively attached over the outlet port of an ink tank.
A problem that can occur when removing a seal that is adhered around the outlet port is that it can be difficult for the user to remove the seal in a controllable fashion. Particularly if the seal is removed rapidly, a sticking of the seal and then sudden release as it is pulled off can cause ink on the seal to be flung off. The ink spatter can get on the user's hands or clothing.
Consequently, a need exists for an ink tank that facilitates easy and clean removal of the seal prior to installation onto the printhead.